Imports System.Drawing.Drawing2D

Public Class Form1

    Private PointList As New List(Of PointF)()
    Private pointIndex As Integer = 0
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        SetStyle(ControlStyles.UserPaint, True)
        SetStyle(ControlStyles.AllPaintingInWmPaint, True)
        SetStyle(ControlStyles.DoubleBuffer, True)

        Dim pt As PointF() = New PointF() {New PointF(100, 100), New PointF(150, 150), New PointF(200, 100), New PointF(100, 100)}

        Dim curDist As Single = 0
        Dim distance As Single = 0
        For i As Integer = 0 To pt.Length - 2
            Dim ptA As PointF = pt(i)
            Dim ptB As PointF = pt(i + 1)
            Dim deltaX As Single = ptB.X - ptA.X
            Dim deltaY As Single = ptB.Y - ptA.Y
            curDist = 0
            distance = CSng(Math.Sqrt(Math.Pow(deltaX, 2) + Math.Pow(deltaY, 2)))
            While curDist < distance
                curDist += 1
                Dim offsetX As Single = CSng((CDbl(curDist) / CDbl(distance) * CDbl(deltaX)))
                Dim offsetY As Single = CSng((CDbl(curDist) / CDbl(distance) * CDbl(deltaY)))
                PointList.Add(New PointF(ptA.X + offsetX, ptA.Y + offsetY))
            End While
        Next
    End Sub

    Private Sub Form1_Paint(ByVal sender As System.Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint
        e.Graphics.SmoothingMode = SmoothingMode.AntiAlias
        For i As Integer = 0 To pointIndex - 1
            e.Graphics.DrawLine(Pens.Black, PointList(i).X, PointList(i).Y, PointList(i + 1).X, PointList(i + 1).Y)
        Next
    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        If pointIndex < PointList.Count - 1 Then
            pointIndex += 1
            Me.Refresh()
        End If
    End Sub
End Class